The indictments shed no new light on possible motives behind the Dec. 6 fires, which damaged or destroyed 26 homes under construction in the Hunters Brooke subdivision near the town of Indian Head.
"Who knows what people are thinking when they do something like this," said Charles County Sheriff Frederick Davis. "You have some crimes where you never know what the motive is."
U.S. Attorney Allen F. Loucks, who announced the indictments at a news conference yesterday, said state, local and federal authorities are continuing to investigate and that additional charges and more arrests are possible.
The five men indicted yesterday - all arrested between Dec. 16 and Dec. 20 on federal complaints accusing them of malicious destruction by fire of property involved in interstate commerce - are charged with arson, conspiracy to commit arson and aiding and abetting.
They are: Patrick Steven Walsh, 20, of Fort Washington; Aaron Lee Speed, 21, of Waldorf; Michael M. Everhart, 20, of Waldorf; Jeremy Daniel Parady, 20, of Accokeek, and Roy T. McCann, 22, of Marbury.
The five-count grand jury indictment alleges that from about Aug. 1 to Dec. 6, the five "conspired with one another and other persons known and unknown to the grand jury to maliciously damage and attempt to damage by means of fire residential dwellings under construction" in Hunters Brooke.
The maximum penalty for arson and conspiracy is five to 25 years in prison and a $250,000 fine.
Everhart and McCann were released to home detention last month pending trial, while the others remain in custody as they await further court proceedings.
Loucks declined comment on Gilbert's status. Gilbert's court-appointed attorney, Robert C. Bonsib, also declined to comment. He said he had just been assigned yesterday to represent Gilbert.
At least four of the men were members of a street racing group known variously as "The Family" and the "Unseen Cavaliers."
Kevin Perkins, special agent in charge of the FBI's Baltimore field office, said investigators were able to establish the "who, what, when, where and how" - but not the "why" - of the fires. "We're continuing to look at the why," he said.
Various possible motives for the fires have been discussed.
According to court papers filed by investigators, Gilbert described Walsh as the ringleader of "The Family" and said Walsh told him of plans to set something on fire to increase the group's notoriety.
Some of those charged, including Speed, a security guard, were known to have had grievances against businesses associated with Hunters Brooke.
The search warrant for Walsh's house had authorized investigators to seize "any evidence of a racial nature" that might indicate an affiliation with white supremacists or other extremist groups.
Loucks declined comment when asked why authorities suspect Walsh might have an association with racist groups. But Walsh's attorney, William Purpura, said yesterday his client has no such affiliations.
"There is nothing in his background or in his family's background which is indicative of race hate," Purpura said.